I really hit the jackpot with my "refurbish" question- Lots of very good
commentary, and some advice. However, I feel the need to make a few
comments myself, with regard to the "force" situation that the thread
changed into.
First- the design of the bearing is NOT that of a thrust bearing, it is a
combined load bearing, meant to take both in-line and lateral forces, so
long as they are not very large.
Second- it is not a good idea to assign one job to two devices, as- taking
the vertical load out on both the Rotor and a bearing. any misalignment or
distortion makes the two fight, to the detriment of both.
My intention is to use this bearing as a lateral locator in the LARGE hole
in the tower top. This provides a longer moment-arm for the bending
forces, and reduces some of the loads on the Rotor. To do this best, there
does not need to be a tight fit between the mast and the bearing. This is
in keeping with several comments made by various people.
In this light- I have made an interesting discovery-- while examining the
thing, I put it together, without the balls. The cast surfaces make for a
rough, gritty feeling when you rotate it- HOWEVER- there is an interesting
situation that happens when you turn the base upside-down, and put the mast
collar on it- All the mating surfaces are machined, and there is only a
small amount of "slop" between the parts. The ball-race housing on the
base will fit into the hole on the tower top, and the resulting assembly,
without the balls, can be used as a lateral positioner, in keeping with the
use I mentioned in the paragraph above.
To a real Engineer- "sneaky" is not a dirty word.
Bill
Bill Aycock W4BSG
Jackson County, AL
EM64vr
W4BSG is "vanity" this time, but was
earned by exam in 1954, the first time.
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